.TH std::chrono::year_month_day_last 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::chrono::year_month_day_last \- std::chrono::year_month_day_last

.SH Synopsis
   Defined in header <chrono>
   class year_month_day_last;  \fI(since C++20)\fP

   The class year_month_day_last represents the last day of a specific year and month.
   It is a field-based time point, with a resolution of std::chrono::days, subject to
   the limit that it can only represent the last day of a month.

   std::chrono::years- and std::chrono::months-oriented arithmetic are supported
   directly. An implicit conversion to std::chrono::sys_days allows
   std::chrono::days-oriented arithmetic to be performed efficiently.

   year_month_day_last is a TriviallyCopyable StandardLayoutType.

.SH Member functions

   constructor         constructs a year_month_day_last object
                       \fI(public member function)\fP
   operator+=          modifies the time point by some number of months or years
   operator-=          \fI(public member function)\fP
   year
   month               accesses the fields of this object
   day                 \fI(public member function)\fP
   month_day_last
   operator sys_days   converts to a std::chrono::time_point
   operator local_days \fI(public member function)\fP
   ok                  checks whether this object represents a valid date
                       \fI(public member function)\fP

   Nonmember functions

   operator==  compares two year_month_day_last values
   operator<=> \fI(function)\fP
   (C++20)
   operator+   adds or subtracts a year_month_day_last and some number of years or
   operator-   months
   (C++20)     \fI(function)\fP
   operator<<  outputs a year_month_day_last into a stream
   (C++20)     \fI(function template)\fP

.SH Helper classes

                                                    formatting support for
   std::formatter<std::chrono::year_month_day_last> year_month_day_last
   (C++20)                                          \fI(class template specialization)\fP

   std::hash<std::chrono::year_month_day_last>      hash support for
   (C++26)                                          std::chrono::year_month_day_last
                                                    \fI(class template specialization)\fP

.SH Example


// Run this code

 #include <chrono>
 #include <iostream>

 int main()
 {
     const auto ymd = std::chrono::year_month_day
     {
         std::chrono::floor<std::chrono::days>(std::chrono::system_clock::now())
     };

     const std::chrono::year_month_day_last ymdl
     {
         ymd.year(), ymd.month() / std::chrono::last
     };

     std::cout << "The last day of present month (" << ymdl << ") is: "
               << std::chrono::year_month_day{ymdl}.day() << '\\n';

     // The 'last' object can be placed wherever it is legal to place a 'day':
     using namespace std::chrono;
     constexpr std::chrono::year_month_day_last
         ymdl1 = 2023y / February / last,
         ymdl2 = last / February / 2023y,
         ymdl3 = February / last / 2023y;
     static_assert(ymdl1 == ymdl2 && ymdl2 == ymdl3);
 }

.SH Possible output:

 The last day of present month (2023/Aug/last) is: 31

.SH See also

   year_month_day represents a specific year, month, and day
   (C++20)        \fI(class)\fP
